Published Mar 27, 2023
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The .hashCode() method returns an integer hash code value for the object on which it is invoked. The hash code for a String object is computed as follows:

s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]

s[i] is the i-th character of the string, n is the length of the string, and ^ indicates exponentiation.


int hashCodeValue = objectName.hashCode();
  • hashCodeValue is an integer variable that stores the hash code value returned by the .hashCode() method.


The example below demonstrates the use of the .hashCode() method:

// Example.java
public class Example {
public static void main(String[] args) {
String str = "codeacademy.com";
int hashCodeValue = str.hashCode();

This outputs the following:


Note: The hash code value may vary for the same object when the program is executed multiple times. This is because the hash code value is generated based on the object’s memory address, which may vary each time the program is run due to the dynamic nature of memory allocation in computer systems.

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